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This issue allows a malicious server to cause the client to read large amounts of data into memory, potentially causing memory allocations errors, swapping, out-of-memory conditions or even system freezes."], "mitigation": {"lang": "en:us", "value": "Since this vulnerability is triggered when no read amount is specified and the client defaults to using the potentially malicious Content-Length header, developers can mitigate this issue in their code by always imposing an explicit, safe limit on data reads.\nApplications using the http.client.HTTPResponse.read function directly can ensure that read operations specify a byte limit:\n~~~\n...\nmax_safe_read = 10 * 1024 * 1024\ndata = response.read(max_safe_read)\n...\n~~~"}, "name": "CVE-2025-13836", "package_state": [{"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", "package_name": "firefox", "product_name": "Red Hat Enterprise Linux 10"}, {"cpe": "cpe:/o:redhat:enterprise_linux:10", "fix_state": "Fix deferred", 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["https://www.cve.org/CVERecord?id=CVE-2025-13836\nhttps://nvd.nist.gov/vuln/detail/CVE-2025-13836\nhttps://github.com/python/cpython/issues/119451\nhttps://github.com/python/cpython/pull/119454"], "statement": "This issue can only be exploited by Python applications using the http.client.HTTPResponse.read function without the amount parameter, which specifies the read size in bytes. Note that Python libraries may use this function internally and make applications vulnerable. Additionally, vulnerable Python applications must connect to a malicious or compromised server that replies with a very large or crafted Content-Length header to trigger this issue, limiting the exposure of this vulnerability.", "threat_severity": "Moderate"}